Zhang Hai-Yang, Xu Ning
Department of Physics, Yancheng Institute of Technology, Yancheng 224051, People's Republic of China.
J Phys Condens Matter. 2017 May 17;29(19):195601. doi: 10.1088/1361-648X/aa669d. Epub 2017 Mar 14.
In this paper, we theoretically study the behaviors of the magnetic excitations (MEs) in the normal and nematic phases of iron pnictides. The normal state MEs exhibit commensurability to diamond and square-like structure transition with the increase of energy. This structure transition persists in the spin and orbital scenarios of nematic phases, although the MEs show anisotropic behaviors due to the C symmetry breaking induced by the nematic orders. The MEs exhibit distinct energy evolution behaviors between the spin and orbital scenarios of nematicity. For the spin-nematic scenario, the anisotropy of the MEs persists up to the high energy region. In contrast, for the orbital-nematic scenario, it reduces dramatically in the low energy region and is negligible in the high energy region. These distinct behaviors of the MEs are attributed to the different origins between the spin and orbital scenarios of nematic orders.
在本文中，我们从理论上研究了铁基氮化物正常相和向列相中的磁激发行为。随着能量增加，正常态磁激发呈现出与菱形和类方形结构转变的可公度性。尽管由于向列序诱导的C对称性破缺，磁激发表现出各向异性行为，但这种结构转变在向列相的自旋和轨道情形中均持续存在。磁激发在向列性的自旋和轨道情形之间表现出不同的能量演化行为。对于自旋向列情形，磁激发的各向异性一直持续到高能区域。相比之下，对于轨道向列情形，它在低能区域急剧减小，在高能区域可忽略不计。磁激发的这些不同行为归因于向列序的自旋和轨道情形之间的不同起源。
